Crystal detector



Sept. l, 1925. 1,551,845 E. L., POPPER CRYSTAL DETECTOR Filed Nov. 9, 1925 WITNESSES INVENToR E l Lf X `BY gm i av e; las W11, ATTo'RNEy-'s 4 Patented Sept. l, 1925.

UNI-TED sTATEs 1,551,845 PATENT OFFICE.

EMIL L. POPPER, OF NEW YORK, N. Y.

- CRYSTAL DETECTOR.

Application filed November 9, 1923. Serial No. 673,808.

To all whom t may concern.'

Be it known that I, EMIL L. PorrE-n, a citizen of the United States, and a resident of the city of New York, borough of Manhattan, in the county and State of New York, have invented a new and Improved Crystal Detector, of which the Yfollowing is a full, clear, and exact description.

This invention relates to a crystal detector, and has for an objectthe provision of a simple, durable and compactV apparatus which can be used preferably in connection with a support and insures a firm, steady contact whereby the variations in sensitivity to which crystal detectors of the usual types are subjected are avoided.

Another object concerns the provision of a detector unit formed of a minimum number of simple parts which can be readily assembled and disassembled for inspection and repair.

s The invention is illustrated in the dra-wing, in which the Afigure represents a section taken through the support and the detector unit.

The form of the invention shown in the drawing is a preferred form, although it is understood that modifications in lthe construction and arrangementof the parts and in the character of the materials used may be adopted without departing from the spirit of the invention as set forth in the appended claims. y

In accordance with the preferred form of the invention shown in the drawings,fthe unit is mounted on a support or panelboard l. One element of the unit comprises a metallic cup 2 having a rearwardlyy extending stem 3 adapted to extend through the support and clamped thereto by any suitable means, such as nuts 4. Disposed within this metallic cup 2 is a cup-shaped. member 5, preferably of insulating material such as glass. This cup-shaped body portion or member of insulating material is provided with a cover 6 screwed thereinto. A chamber 7 is formed beneath the ,cover 6 within the body of the cupV 5 and'this chambercontains a liquid, which may be any suitable conducting liquid such as mercury. The

insulating body portion 5 is provided with a' bore through which a metallic stem 8 projects. This stem at its outer end is connected to a metallic lining 9 covering the inner end of the insulating body portionl 5 so that a large area of contact is established between the lining 9 and the metallic cup 2 to afford a good lirm contact whereby the circuit between the conducting liquid in the chamber 7 and the cup 2 is very lirmly established. The cover 6 is provided with a bore through which a` stem l0 projects and has mounted in any suitable manner on its inner end a crystal l1, this crystal projecting sufficiently far into the chamber 7 containing the liquid as to contact therewith. The stem 10 on its outer end, outside the cover 6, isy provided' durable, compact unit composed of a minimum number of parts whereby a firm, stable contact is made with the crystal, andk in which kthe mechanical part-s of the circuit are of such ample proportions as always to insure a firm, stable contact throughout, thus avoiding the usual variations in 'sensitivity found with crystal detectors of the general type. y f

What I claim is:--

l. A crystal detector unit which comprises a metallic cup having a stem extending rearwardly therefrom, said stem adapted to be mounted in a bore in a suitable support, a cup-shaped body portion of in- `and the cup-shaped insulating body portion adapted to be inserted in the metallic cup, above mentioned, a cover of insulating material adapted to be fastened onto the insulating body portion, said cover having a bore, a conducting stem in said last-nientioned bore, said stem extending through the bore into the chamber formed within 2. A crystal detector unit which comrises an insulating bod ortion having a chamber therein `containing `a conducting liquid, a crystal y supported within said.

chamber in contact with Said liquid, av conducting stem extendingv from said crystal through the Walls of said body portion, a sec-ond conducting stem extending from said chamber in contact with said liquid through the Walls of said body portion, a. metallic lining surrounding the end of the body portion adjacent the Sccond-1nentioned Stein, a metallic Cup mounted on a suitable support, in which cup said body portion and linincl are firmly mounted to insure a good Contact between the liningand the cup.

3. A crystal detector unit which comprises a body portion of insulatingl material having a chamber therein containing a conducting` liquid, a conducting stein projecting into Said chamber on one Side thereof and supporting a crystal thereon, said crystal being in contact with the Conductingr liquid, and a conducting element extending` into the liquid from another point to mal-:e Contact with said liquid.

EMIL L. POPPER. 

